Add a recipe demonstrating std::cell::Cell for Copy types — get/set/replace/take — and contrast it with the existing Rc<RefCell<T>> recipe: Cell avoids runtime borrow checking and panics by never handing out references, at the cost of only working by-value.
Cell is core/std only, so this fits as an inline skeptic example (Pattern 1) with no new dependency, likely alongside the existing recipes in src/mem/smart_pointers.md. Originally requested in #434 under "Rust patterns".
Add a recipe demonstrating
std::cell::CellforCopytypes —get/set/replace/take— and contrast it with the existingRc<RefCell<T>>recipe:Cellavoids runtime borrow checking and panics by never handing out references, at the cost of only working by-value.Celliscore/stdonly, so this fits as an inline skeptic example (Pattern 1) with no new dependency, likely alongside the existing recipes insrc/mem/smart_pointers.md. Originally requested in #434 under "Rust patterns".